U.S. prosecutors have brought several tax evasion action against people with secret Swiss bank accounts. In U.S. vs. McCarthy, United States District Court, Central District of California, Case no. CR 09-00784, the prosecutors charged that in 2003 McCarthy opened a Swiss bank account in the name of COGS Enterprises Ltd., a Hong Kong entity. McCarthy has agreed to plead guilty to failure to disclose foreign bank accounts. He faces up to five years inprisonment, three years' supervised release, and fines of up to $250,000

The IRS on August 13, 2009 won a ruling by the 1st U.S. Circuit Court of Appeals in U.S. v. Textron that may give the IRS much greater access to internal materials prepared by corporate taxpayers. The case is IRS v. Textron; US Court of Appeals, First Circuit Case No. 07-2631.

U.S. taxpayers who have offshore bank accounts must annually file a form TD F 90-22.1, Report of Foreign Bank and Financial Accounts ("FBAR"). Failure to disclose or false reporting can carry civil and criminal penalties. The U.S. Treasury has implemented a Voluntary Disclosure Program ("VDP"), which allows taxpayers who are delinquent on their filings to make voluntary disclosure and pay taxes and some penalties by Sept. 23, 2009, to avoid facing criminal charges and imprisonment.